Olefin polymerization catalyst composition comprising group 13 compound

ABSTRACT

Catalyst compositions that are highly tolerant of catalyst poisons comprising a catalytic derivative of a Group 4 metallocene metal complex and an Group 13 metal compound according to the formula R 1   2  M&#34;(NR 2   2 ), 
     wherein R 1  and R 2  independently each occurrence is a hydrocarbyl, silyl, halocarbyl, halohydrocarbyl, hydrocarbyl-substituted silyl, halocarbyl-substituted silyl, or halohydrocarbyl-substituted silyl group, said R 1  and R 2  having from 1 to 30 carbon, silicon, or mixtures of carbon and silicon atoms, and 
     M&#34; is a Group 13 metal, 
     the molar ratio of complex to Group 13 compound being from 1:0.1 to 1:100.

This application claims the benefit of U.S. Provisional Application No.60/022,061 filed Jul. 23, 1996.

This invention relates to compositions of matter which are useful asaddition polymerization catalysts, to a method for preparing thesecatalyst compositions and to a method of using these catalystcompositions. More particularly, this invention relates to improvedolefin polymerization catalyst compositions comprising a Group 4 metalcomplex and a Group 13 amide or silylamide and to an improved method forpolymerizing addition polymerizable monomers using the same.

Constrained geometry metal complexes, their preparation, methods ofactivation, active catalysts formed therefrom including cationiccatalysts and methods of use are disclosed in EP-A-416,815;EP-A-514,828; EP-A-520,732; U.S. Pat. No. 5,064,802; U.S. Pat. No.5,374,696; U.S. Pat. No. 5,470,993; U.S. Pat. No. 5,055,438, U.S. Pat.No. 5,057,475, U.S. Pat. No. 5,096,867, U.S Pat. No. 5,064,802, U.S.Pat. No. 5,132,380, and U.S. Pat. No. 5,453,410. For the teachingscontained therein, the aforementioned United States patents andpublished European Patent Applications are herein incorporated in theirentirety by reference thereto.

Although previously known active catalysts, especially the cationiccatalysts disclosed in the foregoing applications and publications, haveexcellent activity, they are extremely sensitive to catalyst poisons,such as polar impurities, that may be contained in a polymerizationmixture. Because of this fact, catalyst efficiencies and lifetimes havebeen limited and molecular weights of the resulting polymers have beenreduced.

It is previously known in the art to utilize adjuvants such astrialkylboron and trialkylaluminum compounds to remove catalyst poisonsfrom biscyclopentadienyl containing olefin polymerization catalysts.Disadvantageously however, such adjuvants have proven to be lesseffective in combating the inhibition of catalytically activatedconstrained geometry catalysts, and when used in the polymerization ofolefin monomers, actually may interfere with the desired catalyticprocess. The previously disclosed U.S. Pat. No. 5,453,410 disclosed thecombination of an alumoxane adjuvant with a cationic constrainedgeometry catalyst composition. However, alumoxanes are rather lesssoluble than is desired in aliphatic hydrocarbon solvents used in commonpolymerization systems. Additionally, alumoxanes are pyrophoric and arerelatively expensive. Thus, it would be desirable to reduce the quantityof alumoxane used in a polymerization process or more desirably still,to eliminate use of alumoxanes entirely. Instead it would be desirableto utilize an adjuvant which is not pyrophoric and is more soluble inaliphatic hydrocarbons.

Finally, components in polymerization processes or their reactionproducts ultimately become incorporated into the polymer produced by thepolymerization process unless a technique for their removal isavailable. Alumoxanes are relatively high molecular weight polymericaluminum oxide compounds. Their presence in residual quantities in thepolymerization product is generally not considered to be beneficial topolymer properties, and may actually degrade some polymer properties,particularly polymer clarity.

The present investigations have led to certain improved catalystcompositions that are highly active as addition polymerizationcatalysts, desirably having improved resistance to catalyst poisons, andimproved efficiency.

According to the present invention there is now provided a catalystcomposition comprising in combination:

a) a metal complex corresponding to the formula: C_(pI) MX_(p) L_(q),

that has been or subsequently is rendered catalytically active bycombination with an activating cocatalyst or by use of an activatingtechnique,

wherein: M is a metal of Group 4 of the Periodic Table of the Elementshaving an oxidation state of +2, +3 or +4, bound in an η⁵ bonding modeto one or more C_(p) groups;

C_(p) independently each occurrence is a cyclopentadienyl-, indenyl-,tetrahydroindenyl-, fluorenyl-, tetrahydrofluorenyl-, oroctahydrofluorenyl-group optionally substituted with from 1 to 8substituents independently selected from the group consisting ofhydrocarbyl, halo, halohydrocarbyl, aminohydrocarbyl, hydrocarbyloxy,dihydrocarbylamino, dihydrocarbylphosphino, silyl, aminosilyl,hydrocarbyloxysilyl, and halosilyl groups containing up to 20non-hydrogen atoms, or further optionally two such C_(p) groups may bejoined together by a divalent substituent selected from hydrocarbadiyl,halohydrocarbadiyl, hydrocarbyleneoxy, hydrocarbyleneamino, siladiyl,halosiladiyl, and divalent aminosilane, groups containing up to 20non-hydrogen atoms;

X independently each occurrence is a monovalent anionic σ-bonded ligandgroup, a divalent anionic σ-bonded ligand group having both valencesbonded to M, or a divalent anionic σ-bonded ligand group having onevalency bonded to M and one valency bonded to a C_(p) group, said Xcontaining up to 60 nonhydrogen atoms;

L independently each occurrence is a neutral Lewis base ligatingcompound, having up to 20 atoms;

I is one or two;

p is 0, 1 or 2, and is I less than the formal oxidation state of M whenX is an monovalent anionic σ-bonded ligand group or a divalent anionicσ-bonded ligand group having one valency bonded to M and one valencybonded to a C_(p) group, or p is I+1 less than the formal oxidationstate of M when X is a divalent anionic σ-bonded ligand group havingboth valencies bonded to M; and

q is 0, 1 or 2; and

b) a Group 13 compound according to the formula

    R.sup.1.sub.2 M"(NR.sup.2.sub.2),

wherein R¹ and R² independently each occurrence is a hydrocarbyl, silyl,halocarbyl, halohydrocarbyl, hydrocarbyl-substituted silyl,halocarbyl-substituted silyl, or halohydrocarbyl-substituted silylgroup, said R¹ and R² having from 1 to 30 carbon, silicon, or mixturesof carbon and silicon atoms, and

M" is a Group 13 metal,

the molar ratio of a):b) being from 1:0.1 to 1:100;

or the resulting derivative, reaction product or equilibrium mixtureresulting from such combination.

Further according to the present invention there is provided a processfor polymerization of addition polymerizable monomers or mixturesthereof comprising contacting said monomer or mixture of monomers with acatalyst system comprising the above catalyst composition under additionpolymerization conditions. Preferred addition polymerizable monomersinclude C₂₋₂₀,000 σ-olefins. Polymers prepared by the foregoing inventedprocess are usefully employed for molding, film, sheet, extrusionfoaming and other applications.

All references to the Periodic Table of the Elements herein shall referto the Periodic Table of the Elements, published and copyrighted by CRCPress, Inc., 1989. Also, any reference to a Group or Groups shall be tothe Group or Groups as reflected in this Periodic Table of the Elementsusing the IUPAC system for numbering groups.

The compositions of the present invention are believed to exist in theform of a mixture of one or more cationic, zwitterionic or othercatalytically active species derived from the foregoing metal complex a)in combination with the Group 13 compound, b), or alternatively, amixture of the metal complex or a cationic, zwitterionic or othercatalytically active derivative thereof with a derivative formed byinteraction of the Group 13 compound with the cocatalyst. Fully cationicor partially charge separated metal complexes, that is, zwitterionicmetal complexes, have been previously disclosed in U.S. Pat. Nos.5,470,993 and 5,486,632, the teachings of which are herein incorporatedin their entirety by reference thereto. Derivatives of the Group 13compound and cocatalyst may arise, for example, by ligand exchange. Inparticular, where the cocatalyst is a strong Lewis acid, such astris(fluorophenyl)borane, some quantity of fluorophenyl substituents mayexchange with the ligand groups of the Group 13 compound to formfluorophenyl substituted derivatives thereof.

The cationic complexes are believed to correspond to the formula: C_(pI)M⁺ X_(p-1) A⁻ wherein:

M is a Group 4 in the +4 or +3 formal oxidation state;

C_(p), X, I and p are as previously defined; and

A⁻ is a noncoordinating, compatible anion derived from the activatingcocatalyst.

The zwitterionic complexes in particular result from activation of aGroup 4 metal diene complex that is in the form of ametallocyclopentene, wherein the metal is in the +4 formal oxidationstate, (that is X is 2-butene-1,4-diyl, or a hydrocarbyl substitutedderivative thereof, having both valencies bonded to M) by the use of aLewis acid activating cocatalyst, especially tris(perfluoroaryl)boranes.These zwitterionic complexes are believed to correspond to the formula:C_(pI) M⁺ X_(p-1) L**-A⁻ wherein:

M is a Group 4 metal in the +4 formal oxidation state;

C_(p), X, I and p are as previously defined;

L** is the divalent remnant of the conjugated diene, X', formed by ringopening at one of the carbon to metal bonds of a metallocyclopentene;and

A⁻ is a noncoordinating, compatible anion derived from the activatingcocatalyst.

As used herein, the recitation "noncoordinating" means an anion whicheither does not coordinate to component a) or which is only weaklycoordinated therewith remaining sufficiently labile to be displaced by aneutral Lewis base, including an α-olefin. A non-coordinating anionspecifically refers to an anion which when functioning as a chargebalancing anion in the catalyst system of this invention, does nottransfer a fragment thereof to said cation thereby forming a neutralfour coordinate metal complex and a neutral byproduct. "Compatibleanions" are anions which are not degraded to neutrality when theinitially formed complex decomposes and are noninterfering with desiredsubsequent polymerizations.

Preferred L groups are phosphines, especially trimethylphosphine,triethylphosphine, triphenylphosphine andbis(1,2-dimethylphosphino)ethane; P(OR)₃, wherein R is as previouslydefined; ethers, especially tetrahydrofuran; amines, especiallypyridine, bipyridine, tetramethylethylenediamine (TMEDA), andtriethylamine; olefins; and conjugated dienes having from 4 to 40 carbonatoms. Complexes including conjugated diene L groups include thosewherein the metal is in the +2 formal oxidation state.

Examples of coordination complexes a) used according to the presentinvention include the foregoing species: ##STR1## wherein: M istitanium, zirconium or hafnium, preferably zirconium or hafnium, in the+2 or +4 formal oxidation state;

R³ in each occurrence independently is selected from the groupconsisting of hydrogen, hydrocarbyl, silyl, germyl, cyano, halo andcombinations thereof, said R³ having up to 20 non-hydrogen atoms, oradjacent R³ groups together form a divalent derivative (i.e., ahydrocarbadiyl, siladiyl or germadiyl group) thereby forming a fusedring system,

X" independently each occurrence is an anionic ligand group of up to 40non-hydrogen atoms, or two X" groups together form a divalent anionicligand group of up to 40 non-hydrogen atoms or together are a conjugateddiene having from 4 to 30 non-hydrogen atoms forming a π-complex with M,whereupon M is in the +2 formal oxidation state,

R* independently each occurrence is C₁₋₄ alkyl or phenyl,

E independently each occurrence is carbon or silicon, and

x is an integer from 1 to 8.

Additional examples of metal complexes a) include those corresponding tothe formula: C_(p) MX_(p) L_(q) (III) wherein C_(p), M, X, L, p and qare as previously defined. A preferred metal complex belongs to theforegoing class (III) and corresponds to the formula: ##STR2## wherein:M is titanium, zirconium or hafnium in the +2, +3 or +4 formal oxidationstate;

R³ in each occurrence independently is selected from the groupconsisting of hydrogen, hydrocarbyl, silyl, germyl, cyano, halo andcombinations thereof, said R³ having up to 20 non-hydrogen atoms, oradjacent R³ groups together form a divalent derivative (i.e., ahydrocarbadiyl, siladiyl or germadiyl group) thereby forming a fusedring system,

each X" is a halo, hydrocarbyl, hydrocarbyloxy, hydrocarbylamino, orsilyl group, said group having up to 20 non-hydrogen atoms, or two X"groups together form a neutral C₅₋₃₀ conjugated diene or a divalentderivative thereof;

E* is --O--, --S--, --NR*--, --PR*--;

Z is SiR*₂, CR*₂, SiR*₂ SiR*₂, CR*₂ CR*₂, CR*═CR*, CR*₂ SiR*₂, or GeR*₂,wherein R* is as previously defined, and

n is an integer from 1 to 3.

Most preferred coordination complexes a) used according to the presentinvention are complexes corresponding to the formula: ##STR3## wherein:R³ independently each occurrence is a group selected from hydrogen,hydrocarbyl, halohydrocarbyl, silyl, germyl and mixtures thereof, saidgroup containing up to 20 nonhydrogen atoms;

M is titanium, zirconium or hafnium;

Z, E*, X and L are as previously defined;

p is 0, 1 or 2; and

q is zero or one;

with the proviso that:

when p is 2, q is zero, M is in the +4 formal oxidation state, and X isan anionic ligand selected from the group consisting of halide,hydrocarbyl, hydrocarbyloxy, di(hydrocarbyl)amido,di(hydrocarbyl)phosphido, hydrocarbylsulfido, and silyl groups, as wellas halo-, di(hydrocarbyl)amino-, hydrocarbyloxy- anddi(hydrocarbyl)-phosphino-substituted derivatives thereof, said X grouphaving up to 20 nonhydrogen atoms,

when p is 1, q is zero, M is in the +3 formal oxidation state, and X isa stabilizing anionic ligand group selected from the group consisting ofallyl, 2-(N,N-dimethylaminomethyl)phenyl, and2-(N,N-dimethyl)-aminobenzyl, or M is in the +4 formal oxidation state,and X is a divalent derivative of a conjugated diene, M and X togetherforming a metallocyclopentene group, and

when p is 0, q is 1, M is in the +2 formal oxidation state, and L is aneutral, conjugated or nonconjugated diene, optionally substituted withone or more hydrocarbyl groups, said L having up to 40 carbon atoms andforming a π-complex with M.

More preferred coordination complexes a) used according to the presentinvention are complexes corresponding to the formula: ##STR4## wherein:R³ independently each occurrence is hydrogen or C₁₋₆ alkyl;

M is titanium;

E*X is --O--, --S--, --NR*--, --PR*--;

Z* is SiR*₂, CR*₂, SiR*₂ SiR*₂, CR*₂ CR*₂, CR*═CR*, CR*₂ SiR*₂, or GeR*₂;

R* each occurrence is independently hydrogen, or a member selected fromhydrocarbyl, hydrocarbyloxy, silyl, halogenated alkyl, halogenated aryl,and combinations thereof, said R* having up to 20 non-hydrogen atoms,and optionally, two R* groups from Z (when R* is not hydrogen), or an R*group from Z and an R* group from E* form a ring system;

p is 0, 1 or 2;

q is zero or one;

with the proviso that:

when p is 2, q is zero, M is in the +4 formal oxidation state, and X isindependently each occurrence methyl or benzyl,

when p is 1, q is zero, M is in the +3 formal oxidation state, and X is2-(N,N-dimethyl)aminobenzyl; or M is in the +4 formal oxidation stateand X is 2-butene-1,4-diyl, and

when p is 0, q is 1, M is in the +2 formal oxidation state, and L is1,4-diphenyl-1,3-butadiene or 1,3-pentadiene. The latter diene isillustrative of unsymetrical diene groups that result in production ofmetal complexes that are actually mixtures of the respective geometricalisomers.

The complexes can be prepared by use of well known synthetic techniques.A preferred process for preparing the metal complexes is disclosed inU.S. Ser. No. 8/427,378, filed Apr. 24, 1995, the teachings of which arehereby incorporated by reference. The reactions are conducted in asuitable noninterfering solvent at a temperature from -100 to 300° C.,preferably from -78 to 100° C., most preferably from 0 to 50° C. Areducing agent may be used to cause the metal M, to be reduced from ahigher to a lower oxidation state. Examples of suitable reducing agentsare alkali metals, alkaline earth metals, aluminum and zinc, alloys ofalkali metals or alkaline earth metals such as sodium/mercury amalgamand sodium/potassium alloy, sodium naphthalenide, potassium graphite,lithium alkyls, lithium or potassium alkadienyls, and Grignard reagents.

Suitable reaction media for the formation of the complexes includealiphatic and aromatic hydrocarbons, ethers, and cyclic ethers,particularly branched-chain hydrocarbons such as isobutane, butane,pentane, hexane, heptane, octane, and mixtures thereof; cyclic andalicyclic hydrocarbons such as cyclohexane, cycloheptane,methylcyclohexane, methylcycloheptane, and mixtures thereof; aromaticand hydrocarbyl-substituted aromatic compounds such as benzene, toluene,and xylene, C₁₋₄ dialkyl ethers, C₁₋₄ dialkyl ether derivatives of(poly)alkylene glycols, and tetrahydrofuran. Mixtures of the foregoingare also suitable.

Suitable activating cocatalysts useful in combination with component a)are those compounds capable of abstraction of an X substituent therefromto form an inert, noninterfering counter ion, or that form azwitterionic or other catalytically active derivative of a). Suitableactivating cocatalysts for use herein include perfluorinatedtri(aryl)boron compounds, and most especiallytris(pentafluorophenyl)borane; nonpolymeric, compatible,noncoordinating, ion forming compounds (including the use of suchcompounds under oxidizing conditions), especially the use of ammonium-,phosphonium-, oxonium-, carbonium-, silylium- or sulfonium- salts ofcompatible, noncoordinating anions, and ferrocenium salts of compatible,noncoordinating anions. Suitable activating techniques include the useof bulk electrolysis (explained in more detail hereinafter). Acombination of the foregoing activating cocatalysts and techniques maybe employed as well. The foregoing activating cocatalysts and activatingtechniques have been previously taught with respect to different metalcomplexes in the following references: EP-A-277,003, U.S. Pat. No.5,153,157, U.S. Pat. No. 5,064,802, U.S. Pat. No. 5,321,106,EP-A-520,732; and U.S. Pat. No. 5,350,723, the teachings of which arehereby incorporated by reference.

More particularly, suitable ion forming compounds useful as cocatalystsin one embodiment of the present invention comprise a cation which is aBronsted acid capable of donating a proton, and a compatible,noncoordinating anion, A- . As used herein, the term "noncoordinating"means an anion or substance which either does not coordinate to theGroup 4 metal containing precursor complex and the catalytic derivativederived therefrom, or which is only weakly coordinated to such complexesthereby remaining sufficiently labile to be displaced by a neutral Lewisbase. "Compatible anions" are anions which are not degraded toneutrality when the initially formed complex decomposes and arenoninterfering with desired subsequent polymerization or other uses ofthe complex.

Preferred anions are those containing a single coordination complexcomprising a charge-bearing metal or metalloid core which anion iscapable of balancing the charge of the active catalyst species (themetal cation) which may be formed when the two components are combined.Also, said anion should be sufficiently labile to be displaced byolefinic, diolefinic and acetylenically unsaturated compounds or otherneutral Lewis bases such as ethers or nitrites. Suitable metals include,but are not limited to, aluminum, gold and platinum. Suitable metalloidsinclude, but are not limited to, boron, phosphorus, and silicon.Compounds containing anions which comprise coordination complexescontaining a single metal or metalloid atom are, of course, well knownand many, particularly such compounds containing a single boron atom inthe anion portion, are available commercially.

Preferably such cocatalysts may be represented by the following generalformula:

    (L*-H).sup.+.sub.d (A).sup.d-

wherein:

L* is a neutral Lewis base;

(L*-H)+ is a Bronsted acid;

A^(d-) is a noncoordinating, compatible anion having a charge of d-, and

d is an integer from 1 to 3.

More preferably A^(d-) corresponds to the formula: [M^(I) Q₄ ]⁻ ;wherein:

M^(I) is boron or aluminum in the +3 formal oxidation state; and

Q independently each occurrence is selected from hydride, dialkylamido,halide, hydrocarbyl, hydrocarbyloxide, halosubstituted-hydrocarbyl,hydroxy-substituted hydrocarbyl, halosubstituted hydrocarbyloxy, andhalo-substituted silylhydrocarbyl radicals (including perhalogenatedhydrocarbyl-perhalogenated hydrocarbyloxy-and perhalogenatedsilylhydrocarbyl radicals), said Q having up to 20 carbons with theproviso that in not more than one occurrence is Q halide. Examples ofsuitable hydrocarbyloxide Q groups are disclosed in U.S. Pat. No.5,296,433, the teachings of which are herein incorporated by reference.

In a more preferred embodiment, d is one, that is, the counter ion has asingle negative charge and is A⁻. Activating cocatalysts comprisingboron which are particularly useful in the preparation of catalysts ofthis invention may be represented by the following general formula:(L*-H)⁺ (BQ₄)⁻ ; wherein:

L* is as previously defined;

B is boron in a formal oxidation state of 3; and

Q is a hydrocarbyl-, hydrocarbyloxy-, fluorinated hydrocarbyl-,fluorinated hydrocarbyloxy-, or fluorinated silylhydrocarbyl- group ofup to 20 nonhydrogen atoms, with the proviso that in not more than oneoccasion is Q hydrocarbyl.

Most preferably, Q is each occurrence a fluorinated aryl group,especially, a pentafluorophenyl group.

Illustrative, but not limiting, examples of boron compounds which may beused as an activating cocatalyst in the preparation of the improvedcatalysts of this invention are tri-substituted ammonium salts such as:

trimethylammonium tetrakis(pentafluorophenyl) borate,

triethylammonium tetrakis(pentafluorophenyl) borate,

tripropylammonium tetrakis(pentafluorophenyl) borate,

tri(n-butyl)ammonium tetrakis(pentafluorophenyl) borate,

tri(sec-butyl)ammonium tetrakis(pentafluorophenyl) borate,

N,N-dimethyl-N-dodecylammonium tetrakis(pentafluorophenyl) borate,

N,N-dimethyl-N-octadecylammonium tetrakis(pentafluorophenyl) borate,

N-methyl-N,N-didodecylammonium tetrakis(pentafluorophenyl) borate,

N-methyl-N,N-dioctadecylammonium tetrakis(pentafluorophenyl) borate,

N,N-dimethylanilinium tetrakis(pentafluorophenyl) borate,

N,N-dimethylanilinium n-butyltris(pentafluorophenyl) borate,

N,N-dimethylanilinium benzyltris(pentafluorophenyl) borate,

N,N-dimethylanilinium tetrakis(4-(t-butyldimethylsilyl)-2, 3, 5,6-tetrafluorophenyl) borate,

N,N-dimethylanilinium tetrakis(4-(triisopropylsilyl)-2, 3, 5,6-tetrafluorophenyl) borate,

N,N-dimethylanilinium pentafluorophenoxytris(pentafluorophenyl) borate,

N,N-diethylanilinium tetrakis(pentafluorophenyl) borate,

N,N-dimethyl-2,4,6-trimethylanilinium tetrakis(pentafluorophenyl)borate,

trimethylammonium tetrakis(2,3,4,6-tetrafluorophenyl) borate,

triethylammonium tetrakis(2,3,4,6-tetrafluorophenyl) borate,

tripropylammonium tetrakis(2,3,4,6-tetrafluorophenyl) borate,

tri(n-butyl)ammonium tetrakis(2,3,4,6-tetrafluorophenyl) borate,

dimethyl(t-butyl)ammonium tetrakis(2,3,4,6-tetrafluorophenyl) borate,

N,N-dimethylanilinium tetrakis(2,3,4,6-tetrafluorophenyl) borate,

N,N-diethylanilinium tetrakis(2,3,4,6-tetrafluorophenyl) borate, and

N,N-dimethyl-2,4,6-trimethylaniliniumtetrakis(2,3,4,6-tetrafluorophenyl) borate;

disubstituted ammonium salts such as:

di-(i-propyl)ammonium tetrakis(pentafluorophenyl) borate, and

dicyclohexylammonium tetrakis(pentafluorophenyl) borate;

trisubstituted phosphonium salts such as:

ntriphenylphosphonium tetrakis(pentafluorophenyl) borate,

tri(o-tolyl)phosphonium tetrakis(pentafluorophenyl) borate, and

tri(2,6-dimethylphenyl)phosphonium tetrakis(pentafluorophenyl) borate;

disubstituted oxonium salts such as:

diphenyloxonium tetrakis(pentafluorophenyl) borate,

di(o-tolyl)oxonium tetrakis(pentafluorophenyl) borate, and

di(2,6-dimethylphenyl)oxonium tetrakis(pentafluorophenyl) borate;

disubstituted sulfonium salts such as:

diphenylsulfonium tetrakis(pentafluorophenyl) borate,

di(o-tolyl)sulfonium tetrakis(pentafluorophenyl) borate, and

bis(2,6-dimethylphenyl)sulfonium tetrakis(pentafluorophenyl) borate.

Preferred (L*-H)⁺ cations are N,N-dimethylanilinium, tributylammonium,N-methyl-N,N-di(dodecyl)ammonium, N-methyl-N,N-di(tetradecyl)ammonium,N-methyl-N,N-di(hexadecyl)ammonium, N-methyl-N,N-di(octadecyl)ammonium,and mixtures thereof. The latter three cations are the primary ammoniumcations derived from a commercially available mixture of C₁₄₋₁₈ tallowamines, and are collectively referred to as bis-hydrogenated tallowalkylmethylammonium cation. The resulting ammonium salt of thetetrakis(pentafluorophenyl)borate anion accordingly is know asbis-hydrogenated tallowalkyl methylammoniumtetrakis(pentafluorophenyl)borate.

Another suitable ion forming, activating cocatalyst comprises a salt ofa cationic oxidizing agent and a noncoordinating, compatible anionrepresented by the formula:

    (Ox.sup.e+).sub.d (A.sup.d-).sub.e.

wherein:

Ox^(e+) is a cationic oxidizing agent having a charge of e+;

e is an integer from 1 to 3; and

A^(d-) and d are as previously defined.

Examples of cationic oxidizing agents include: ferrocenium,hydrocarbyl-substituted ferrocenium, Ag⁺ or Pb⁺². Preferred embodimentsof A^(d-) are those anions previously defined with respect to theBronsted acid containing activating cocatalysts, especiallytetrakis(pentafluorophenyl)borate.

Another suitable ion forming, activating cocatalyst comprises a compoundwhich is a salt of a carbenium ion and a noncoordinating, compatibleanion represented by the formula: ©⁺ A⁻ wherein:

©+ is a C₁₋₂₀ carbenium ion; and

A³¹ is as previously defined. A preferred carbenium ion is the tritylcation, i.e. triphenylmethylium.

A further suitable ion forming, activating cocatalyst comprises acompound which is a salt of a silylium ion and a noncoordinating,compatible anion represented by the formula:

    R'.sub.3 Si.sup.+ A.sup.-

wherein:

R'is C₁₋₁₀ hydrocarbyl, and A⁻ are as previously defined.

Preferred silylium salt activating cocatalysts are trimethylsilyliumtetrakispentafluorophenylborate, triethylsilyliumtetrakispentafluorophenylborate and ether substituted adducts thereof.Silylium salts have been previously generically disclosed in J. ChemSoc. Chem. Comm., 1993, 383-384, as well as Lambert, J. B., et al.,Organometallics, 1994, 13, 2430-2443. The use of the above silyliumsalts as activating cocatalysts for addition polymerization catalysts isclaimed in U.S. Ser. No. 08/304,314, filed Sep. 12, 1994.

Certain complexes of alcohols, mercaptans, silanols, and oximes withtris(pentafluorophenyl)borane are also effective catalyst activators andmay be used according to the present invention. Such cocatalysts aredisclosed in U.S. Pat. No. 5,296,433, the teachings of which are hereinincorporated by reference.

The technique of bulk electrolysis involves the electrochemicaloxidation of the metal complex under electrolysis conditions in thepresence of a supporting electrolyte comprising a noncoordinating, inertanion. In the technique, solvents, supporting electrolytes andelectrolytic potentials for the electrolysis are used such thatelectrolysis byproducts that would render the metal complexcatalytically inactive are not substantially formed during the reaction.More particularly, suitable solvents are materials that are: liquidsunder the conditions of the electrolysis (generally temperatures from 0to 100° C.), capable of dissolving the supporting electrolyte, andinert. "Inert solvents" are those that are not reduced or oxidized underthe reaction conditions employed for the electrolysis. It is generallypossible in view of the desired electrolysis reaction to choose asolvent and a supporting electrolyte that are unaffected by theelectrical potential used for the desired electrolysis. Preferredsolvents include difluorobenzene (all isomers), dimethoxyethane (DME),and mixtures thereof.

The electrolysis may be conducted in a standard electrolytic cellcontaining an anode and cathode (also referred to as the workingelectrode and counter electrode respectively). Suitable materials ofconstruction for the cell are glass, plastic, ceramic and glass coatedmetal. The electrodes are prepared from inert conductive materials, bywhich are meant conductive materials that are unaffected by the reactionmixture or reaction conditions. Platinum or palladium are preferredinert conductive materials. Normally an ion permeable membrane such as afine glass frit separates the cell into separate compartments, theworking electrode compartment and counter electrode compartment. Theworking electrode is immersed in a reaction medium comprising the metalcomplex to be activated, solvent, supporting electrolyte, and any othermaterials desired for moderating the electrolysis or stabilizing theresulting complex. The counter electrode is immersed in a mixture of thesolvent and supporting electrolyte. The desired voltage may bedetermined by theoretical calculations or experimentally by sweeping thecell using a reference electrode such as a silver electrode immersed inthe cell electrolyte. The background cell current, the current draw inthe absence of the desired electrolysis, is also determined. Theelectrolysis is completed when the current drops from the desired levelto the background level. In this manner, complete conversion of theinitial metal complex can be easily detected.

Suitable supporting electrolytes are salts comprising a cation and acompatible, noncoordinating anion, A⁻. Preferred supporting electrolytesare salts corresponding to the formula G⁺ A⁻ ; wherein:

G⁺ is a cation which is nonreactive towards the starting and resultingcomplex, and

A⁻ is as previously defined.

Examples of cations, G⁺, include tetrahydrocarbyl substituted ammoniumor phosphonium cations having up to 40 nonhydrogen atoms. Preferredcations are the tetra(n-butylammonium)-and tetraethylammonium-cations.

During activation of the complexes of the present invention by bulkelectrolysis the cation of the supporting electrolyte passes to thecounter electrode and A⁻ migrates to the working electrode to become theanion of the resulting oxidized product. Either the solvent or thecation of the supporting electrolyte is reduced at the counter electrodein equal molar quantity with the amount of oxidized metal complex formedat the working electrode. Preferred supporting electrolytes aretetrahydrocarbylammonium salts of tetrakis(perfluoroaryl) borates havingfrom 1 to 10 carbons in each hydrocarbyl or perfluoroaryl group,especially tetra(n-butylammonium)tetrakis(pentafluorophenyl) borate.

A further recently discovered electrochemical technique for generationof activating cocatalysts is the electrolysis of a disilane compound inthe presence of a source of a noncoordinating compatible anion. All ofthe foregoing techniques are more fully disclosed and claimed in U.S.Pat. No. 5,372,682. In as much as the activation technique ultimatelyproduces a cationic metal complex, the amount of such resulting complexformed during the process can be readily determined by measuring thequantity of energy used to form the activated complex in the process.

The most preferred activating cocatalysts aretrispentafluorophenylborane and a mixture of long chain ammonium saltsof tetrakis(pentafluorophenyl)borate, especiallyN,N-dioctadecyl-N-methylammonium tetrakpentafluorophenylborate andN,N-ditetradecyl-N-methylammonium tetrakpentafluorophenylborate. Thelatter mixture of borate salts is derived from hydrogenated tallowamine, and is referred to as bis-hydrogenated tallowalkyl methylammoniumtetrakis(pentafluorophenyl)borate.

The molar ratio of metal complex: activating cocatalyst employedpreferably ranges from 1:10 to 2:1, more preferably from 1:5 to 1.5:1,most preferably from 1:5 to 1:1.

The Group 13 component, component b) of the catalyst composition of theinvention, preferably corresponds to the formula R¹ ₂ AI(NR² ₂) whereinR¹ and R², independently each occurrence are hydrocarbyl, halocarbyl,halohydrocarbyl, silyl, or hydrocarbyl-substituted silyl radicals offrom 1 to 20 carbon, silicon or mixtures of carbon and silicon atoms,most preferably, methyl, ethyl, isopropyl, t-butyl, benzyl,2,6-di(t-butyl)-4-methylphenyl, and pentafluorophenyl. Most highlypreferred Group 13 compounds include:dimethylaluminum-N,N-dimethylamide, dimethylaluminum-N,N-diethylamide,dimethylaluminum-N,N-diisopropylylamide,dimethylaluminum-N,N-diisobutylamide, diethylaluminum-N,N-dimethylamide,diethylaluminum-N,N-diethylamide,diethylaluminum-N,N-diisopropylylamide,diethylaluminum-N,N-diisobutylamide,diisopropylaluminum-N,N-dimethylamide,diisopropylaluminum-N,N-diethylamide,diisopropylaluminum-N,N-diisopropylylamide,diisopropylaluminum-N,N-diisobutylamide,diisobytylaluminum-N,N-dimethylamide,diisobutylaluminum-N,N-diethylamide,diisobutylaluminum-N,N-diisopropylylamide,diisobutylaluminum-N,N-diisobutylamide,dimethylaluminum-N,N-bis(trimethylsilyl)amide,diethylaluminum-N,N-bis(trimethylsilyl)amide,diisobutylaluminum-N,N-bis(trimethylsilyl)amide,diisobutylaluminum-N,N-bis(trimethylsilyl)amide, and derivatives thereofformed by ligand exchange with fluorophenyl substituted boranecompounds, especially pentafluorophenylborane.

The molar ratio of metal complex to component b) employed in the presentinvention preferably ranges from 1:1 to 1:100, more preferably from 1:1to 1:20, most preferably from 1:1 to 1:10.

The process may be used to polymerize ethylenically unsaturated monomershaving from 2 to 20 carbon atoms either alone or in combination.Preferred monomers include monovinylidene aromatic monomers,4-vinylcyclohexene, vinylcyclohexane, norbornadiene and C₂₋₁₀ aliphaticα-olefins (especially ethylene, propylene, isobutylene, 1-butene,1-hexene, 3-methyl-1-pentene, 4-methyl-1-pentene, and 1-octene), C₄₋₄₀dienes, and mixtures thereof. Of the dienes typically used to prepareEPDMs, the particularly preferred dienes are 1,4-hexadiene (HD),5-ethylidene-2-norbornene (ENB), 5-vinylidene-2-norbornene (VNB),5-methylene-2-norbornene (MNB), and dicyclopentadiene (DCPD). Theespecially preferred dienes are 5-ethylidene-2-norbornene (ENB) and1,4-hexadiene (HD). Most preferred monomers are ethylene, mixtures ofethylene, propylene and ethylidenenorbornene, or mixtures of ethyleneand a C₄₋₈ α-olefin, especially 1-octene.

In general, the polymerization may be accomplished at conditions wellknown in the prior art for Ziegler-Natta or Kaminsky-Sinn typepolymerization reactions, that is, temperatures from 0-250° C.,preferably 30 to 200° C. and pressures from atmospheric to 30,000atmospheres or higher. Suspension, solution, slurry, gas phase, solidstate powder polymerization or other process condition may be employedif desired. A support, especially silica, alumina, or a polymer(especially poly(tetrafluoroethylene) or a polyolefin) may be employed,and desirably is employed when the catalysts are used in a gas phasepolymerization process. The support is preferably employed in an amountto provide a weight ratio of catalyst (based on metal):support from1:100,000 to 1:10, more preferably from 1:50,000 to 1:20, and mostpreferably from 1:10,000 to 1:30.

In most polymerization reactions the molar ratio ofcatalyst:polymerizable compounds employed is from 10⁻¹² :1 to 10⁻¹ :1,more preferably from 10⁻⁹ :1 to 10⁻⁵ :1.

Suitable solvents for polymerization are inert liquids. Examples includestraight and branched-chain hydrocarbons such as isobutane, butane,pentane, hexane, heptane, octane, and mixtures thereof; cyclic andalicyclic hydrocarbons such as cyclohexane, cycloheptane,methylcyclohexane, methylcycloheptane, and mixtures thereof;perfluorinated hydrocarbons such as perfluorinated C₄₋₁₀ alkanes, andthe like and aromatic and alkyl-substituted aromatic compounds such asbenzene, toluene, xylene, ethylbenzene and the like. Suitable solventsalso include liquid olefins which may act as monomers or comonomersincluding ethylene, propylene, butadiene, cyclopentene, 1-hexene,1-hexane, 4-vinylcyclohexene, vinylcyclohexane, 3-methyl-1-pentene,4-methyl-1-pentene, 1,4-hexadiene, 1-octene, 1-decene, styrene,divinylbenzene, allylbenzene, vinyltoluene (including all isomers aloneor in admixture), and the like. Mixtures of the foregoing are alsosuitable.

The catalysts may be utilized in combination with at least oneadditional homogeneous or heterogeneous polymerization catalyst inseparate reactors connected in series or in parallel to prepare polymerblends having desirable properties.

Utilizing the catalyst compositions of the present invention copolymershaving high comonomer incorporation and correspondingly low density, yethaving a low melt index may be readily prepared. That is, high molecularweight polymers are readily attained by use of the present catalystseven at elevated reactor temperatures. This result is highly desirablebecause the molecular weight of α-olefin copolymers can be readilyreduced by the use of hydrogen or similar chain transfer agent, howeverincreasing the molecular weight of α-olefin copolymers is usually onlyattainable by reducing the polymerization temperature of the reactor.Disadvantageously, operation of a polymerization reactor at reducedtemperatures significantly increases the cost of operation since heatmust be removed from the reactor to maintain the reduced reactiontemperature, while at the same time heat must be added to the reactoreffluent to vaporize the solvent. In addition, productivity is increaseddue to improved polymer solubility, decreased solution viscosity, and ahigher polymer concentration. Utilizing the present catalystcompositions, α-olefin homopolymers and copolymers having densities from0.85 g/cm³ to 0.96 g/cm³, and melt flow rates from 0.001 to 10.0 dg/minare readily attained in a high temperature process.

The catalyst compositions of the present invention are particularlyadvantageous for the production of ethylene homopolymers andethylene/α-olefin copolymers having high levels of long chain branching.The use of the catalyst compositions of the present invention incontinuous polymerization processes, especially continuous solutionpolymerization processes, allows for elevated reactor temperatures whichfavor the formation of vinyl terminated polymer chains that may beincorporated into a growing polymer, thereby giving a long chain branch.The use of the present catalyst compositions advantageously allows forthe economical production of ethylene/α-olefin copolymers havingprocessability similar to high pressure, free radical produced lowdensity polyethylene.

The present catalysts system may be advantageously employed to prepareolefin polymers having improved processing properties by polymerizingethylene alone or ethylene/α-olefin mixtures with low levels of a "H"branch inducing diene, such as norbornadiene, 1,7-octadiene, or1,9-decadiene. The unique combination of elevated reactor temperatures,high molecular weight (or low melt indices) at high reactor temperaturesand high comonomer reactivity advantageously allows for the economicalproduction of polymers having excellent physical properties andprocessability. Preferably such polymers comprise ethylene, a C₃₋₂₀α-olefin and a "H"-branching comonomer. Preferably, such polymers areproduced in a solution process, most preferably a continuous solutionprocess.

As previously mentioned, the present catalyst composition isparticularly useful in the preparation of EP and EPDM copolymers in highyield and productivity. The process employed may be either a solution orslurry process both of which are previously known in the art. Kaminsky,J. Poly. Sci., Vol. 23, pp. 2151-64 (1985) reported the use of a solublebis(cyclopentadienyl) zirconium dimethyl-alumoxane catalyst system forsolution polymerization of EP and EPDM elastomers. U.S. Pat. No.5,229,478 disclosed a slurry polymerization process utilizing similarbis(cyclopentadienyl) zirconium based catalyst systems.

The catalyst composition may be prepared as a homogeneous catalyst byaddition of the requisite components to a solvent in whichpolymerization will be carried out by solution polymerizationprocedures. The catalyst system may also be prepared and employed as aheterogeneous catalyst by adsorbing the requisite components on acatalyst support material such as silica gel, alumina or other suitableinorganic support material. When prepared in heterogeneous or supportedform, it is preferred to use silica as the support material. Theheterogeneous form of the catalyst system is employed in a slurrypolymerization. As a practical limitation, slurry polymerization takesplace in liquid diluents in which the polymer product is substantiallyinsoluble. Preferably, the diluent for slurry polymerization is one ormore hydrocarbons with less than 5 carbon atoms. If desired, saturatedhydrocarbons such as ethane, propane or butane may be used in whole orpart as the diluent. Likewise the α-olefin monomer or a mixture ofdifferent α-olefin monomers may be used in whole or part as the diluent.Most preferably the diluent comprises in at least major part theα-olefin monomer or monomers to be polymerized.

In contrast, solution polymerization conditions utilize a solvent forthe respective components of the reaction, particularly the EP or EPDMpolymer. Preferred solvents include mineral oils and the varioushydrocarbons which are liquid at reaction temperatures. Illustrativeexamples of useful solvents include alkanes such as pentane,iso-pentane, hexane, heptane, octane and nonane, as well as mixtures ofalkanes including kerosene and Isopar E™, available from Exxon ChemicalsInc.; cycloalkanes such as cyclopentane and cyclohexane; and aromaticssuch as benzene, toluene, xylenes, ethylbenzene and diethylbenzene.

At all times, the individual ingredients as well as the recoveredcatalyst components must be protected from oxygen and moisture.Therefore, the catalyst components and catalysts must be prepared andrecovered in an oxygen and moisture free atmosphere. Preferably,therefore, the reactions are performed in the presence of an dry, inertgas such as, for example, nitrogen.

Generally the polymerization process is carried out with a differentialpressure of ethylene of from about 10 to about 1000 psi (70 to 7000kPa), most preferably from about 40 to about 400 psi (30 to 300 kPa).The polymerization is generally conducted at a temperature of from 25 to200° C., preferably from 75 to 170° C., and most preferably from greaterthan 95 to 160° C.

The polymerization may be carried out as a batchwise or a continuouspolymerization process A continuous process is preferred, in which eventcatalyst, ethylene, α-olefin, and optionally solvent and diene arecontinuously supplied to the reaction zone and polymer productcontinuously removed therefrom.

The skilled artisan will appreciate that the invention disclosed hereinmay be practiced in the absence of any component which has not beenspecifically disclosed. The following examples are provided as furtherillustration of the invention and are not to be construed as limiting.Unless stated to the contrary all parts and percentages are expressed ona weight basis.

EXAMPLE 1

A stirred 3.8 liter reactor was charged with about 1440 g of lsopar-E™mixed alkanes solvent (available from Exxon Chemicals Inc.) and about130 g of 1 -octene comonomer. Hydrogen (10 mMol) was added as amolecular weight control agent using a mass flow meter. The reactor washeated to the polymerization temperature of 130° C. and saturated withethylene at 450 psig (3.1 MPa). Catalyst ((t-butylamido)dimethyl(η⁵-tetramethylcyclopenta-dienyl)silanetitanium (II) η⁴ -1,3-pentadiene(TI), or bis(n-butylcyclopentadienyl)-zirconium dimethyl (ZR)) andcocatalyst (trispentafluorophenylborane (FAB), bis-hydrogenatedtallowalkyl methylammonium tetrakis(pentafluorophenyl)borate (BFA), orbis-hydrogenated tallowalkyl methylammoniumhydroxyphenyltris(pentafluoro-phenyl)borate (BHI)) were dissolved inIsopar E™ and premixed in a drybox withdiethylaluminum-N,N-diisopropylamide (DEA) ordiisobutylaluminum-N,N-bis(trimethylsilyl)amide (DIB), and transferredto a catalyst addtion system and injected into the reactor overapproximately 4 minutes using a flow of high pressure Isopar E™ solvent.The polymerization conditions were maintained for 10 minutes withethylene supplied on demand to maintain 450 psig reactor pressure. Theethylene consumed during the reaction was monitored using a mass flowmeter and this consumption was used to calculate the catalystefficiency. Results are contained in Table 1.

                                      TABLE 1                                     __________________________________________________________________________        Catalyst          Ratio.sup.1                                                                        Solvent                                                                            1-octene                                                                            Efficiency.sup.2                        Run (μmol)                                                                           Cocatalyst                                                                          Scavenger                                                                           M:B:Al                                                                             (g)  (g)   Kg/g                                    __________________________________________________________________________    1   TI (1.5)                                                                            FAB   DEA   1:3:10                                                                             1437 123   1.2                                     2   "     BFA   "     1:1.5:10                                                                           1417 139   1.7                                     3   "     "     DIB   1:1:5                                                                              1451 131   2.4                                     4   TI (1.0)                                                                            "     "     1:1:10                                                                             1453 132   3.5                                     5   TI (0.75)                                                                           "     "     1:1:15                                                                             1434 128   4.3                                     6   "     "     "     1:1:30                                                                             1448 127   4.3                                     7   TI (1.5)                                                                            BHI   "     1:1:10                                                                             1455 122   1.0                                     8   ZR (1.5)                                                                            BFA   DEA   1:1.5:10                                                                           1409 126   2.1                                     __________________________________________________________________________     .sup.1. molar ratio of metal complex:cocatalyst:scavenger                     .sup.2. Kg of polymer per gram titanium or zirconium                     

What is claimed is:
 1. A catalyst composition comprising incombination:a) a metal complex corresponding to the formula: C_(pI)MX_(p) L_(q) that has been or is rendered catalytically active bycombination with an activating cocatalyst or by use of an activatingtechnique, wherein: M is a metal of Group 4 of the Periodic Table of theElements having an oxidation state of +2, +3 or +4, bound in an η⁵bonding mode to one or two C_(p) groups; C_(p) independently eachoccurrence is a cyclopentadienyl-, indenyl-, tetrahydroindenyl-,fluorenyl-, tetrahydrofluorenyl-, or octahydrofluorenyl-group optionallysubstituted with from 1 to 8 substituents independently selected fromthe group consisting of hydrocarbyl, halo, halohydrocarbyl,aminohydrocarbyl, hydrocarbyloxy, dihydrocarbylamino,dihydrocarbylphosphino, silyl, aminosilyl, hydrocarbyloxysilyl, andhalosilyl groups containing up to 20 non-hydrogen atoms, or furtheroptionally two such C_(p) groups may be joined together by a divalentsubstituent selected from the group consisting of hydrocarbadiyl,halohydrocarbadiyl, hydrocarbyleneoxy, hydrocarbyleneamino, siladiyl,halosiladiyl, and divalent aminosilane groups containing up to 20non-hydrogen atoms; X independently each occurrence is a monovalentanionic σ-bonded ligand group, a divalent anionic σ-bonded ligand grouphaving both valences bonded to M, or a divalent anionic σ-bonded ligandgroup having one valency bonded to M and one valency bonded to a C_(p)group, said X containing up to 60 nonhydrogen atoms; independently eachoccurrence is a neutral Lewis base ligand having up to 20 atoms; I isone or two; p is 0, 1 or 2, and is I less than the formal oxidationstate of M when X is an monovalent anionic σ-bonded ligand group or adivalent anionic σbonded ligand group having one valency bonded to M andone valency bonded to a C_(p) group, or p is I +1 less than the formaloxidation state of M when X is a divalent anionic σ-bonded ligand grouphaving both valencies bonded to M; and q is 0, 1 or 2; and b) a Group 13compound according to the formula R¹ ₂ M"(NR² ₂), wherein R¹ and R²independently each occurrence is a hydrocarbyl, silyl, halocarbyl,halohydrocarbyl, hydrocarbyl-substituted silyl, halocarbyl-substitutedsilyl, or halohydrocarbyl-substituted silyl group, said R¹ and R² eachhaving from 1 to 30 carbon, silicon, or mixtures of carbon and siliconatoms, and M" is a Group 13 metal, the molar ratio of a):b) being from1:0.1 to 1:100; or the resulting derivative, reaction product orequilibrium mixture resulting from such combination.
 2. A catalystcomposition according to claim 1 wherein the Group 13 compoundcorresponds to the formula R¹ ₂ AI(NR² ₂) wherein R¹ and R²,independently each occurrence are hydrocarbyl, halocarbyl,halohydrocarbyl, silyl, or hydrocarbyl-substituted silyl radicals offrom 1 to 20 carbon, silicon or mixtures of carbon and silicon atoms. 3.A catalyst composition according to claim 2 wherein the Group 13compound is dimethylaluminum-N,N-dimethylamide,dimethylaluminum-N,N-diethylamide,dimethylaluminum-N,N-diisopropylylamide,dimethylaluminum-N,N-diisobutylamide, diethylaluminum-N,N-dimethylamide,diethylaluminum-N,N-diethylamide,diethylaluminum-N,N-diisopropylylamide,diethylaluminum-N,N-diisobutylamide,diisopropylaluminum-N,N-dimethylamide,diisopropylaluminum-N,N-diethylamide,diisopropylaluminum-N,N-diisopropylylamide,diisopropylaluminum-N,N-diisobutylamide,diisobytylaluminum-N,N-dimethylamide,diisobutylaluminum-N,N-diethylamide,diisobutylaluminum-N,N-diisopropylylamide,diisobutylaluminum-N,N-diisobutylamide,dimethylaluminum-N,N-bis(trimethylsilyl)amide,diethylaluminum-N,N-bis(trimethylsilyl)amide,diisobutylaluminum-N,N-bis(trimethylsilyl)amide,diisobutylaluminum-N,N-bis(trimethylsilyl)amide, and derivatives thereofformed by ligand exchange with fluorophenyl substituted boranecompounds.
 4. A catalyst composition according to claim 1 wherein themolar ratio of metal complex to component b) is from 1:1 to 1:50.
 5. Acatalyst composition according to claim 1 wherein the activatingcocatalyst comprises trispentafluorophenylborane,N-methyl-N,N-dioctadecylammonium tetrakis(pentafluorophenyl)borate,bis-hydrogenated tallowalkyl methylammoniumtetrakis(pentafluorophenyl)borate, or the derivative resulting fromligand exchange between trispentafluorophenylborane and component b). 6.A process for polymerization of addition polymerizable monomers ormixtures thereof comprising contacting said monomer or mixture ofmonomers with a catalyst system comprising the catalyst composition ofclaim 1 under addition polymerization conditions.
 7. The process ofclaim 6 wherein the addition polymerizable monomer is a C₂₋₂₀ α-olefinor a mixture thereof.
 8. The process of claim 7 wherein the molar ratioof metal complex to component b) is from 1:1 to 1:50 .